{"id":"1a00179e-c645-5e57-9f84-241e38c79d43","stable_key":"ea2f0904-ab2c-5d1e-a3d4-3f7ecdd70cd6:caf-xor-ratio","predicate":"reduces","statement":"In 21 participants, allopurinol reduced urinary 1-methyluric-acid/1-methylxanthine to 15.9% of baseline.","claim_class":"observational","status":"source_derived_draft","evidence_grade":"ungraded","direction":"negative","is_public":true,"mechanism_event_id":"532f0ad7-3227-53e1-8437-3b2525b2efd2","mechanism_event_label":"Blocking a downstream enzyme changed the metabolite pattern.","subject":{"id":"cfa51e26-3627-5a5e-9270-89c53f9db01b","slug":"allopurinol","display_name":"Allopurinol","entity_type_key":"small_molecule"},"object":{"id":"1e50dcc0-966a-56e4-8dec-b2d1e262bfe3","slug":"caffeine-metabolite-ratios","display_name":"Caffeine-derived urinary enzyme-phenotyping ratios","entity_type_key":"cellular_process"},"evidence_count":1,"mechanism_event":{"id":"532f0ad7-3227-53e1-8437-3b2525b2efd2","stable_key":"ea2f0904-ab2c-5d1e-a3d4-3f7ecdd70cd6:caf-xor-ratio-event","event_type":"observed_relationship","label":"Blocking a downstream enzyme changed the metabolite pattern.","description":"In 21 participants, allopurinol reduced urinary 1-methyluric-acid/1-methylxanthine to 15.9% of baseline.","status":"provisional","compartment":null,"participants":[{"entity":{"id":"cfa51e26-3627-5a5e-9270-89c53f9db01b","slug":"allopurinol","display_name":"Allopurinol","entity_type_key":"small_molecule"},"role":"subject","stoichiometry":null,"state_label":"","sequence_order":0,"notes":""},{"entity":{"id":"1e50dcc0-966a-56e4-8dec-b2d1e262bfe3","slug":"caffeine-metabolite-ratios","display_name":"Caffeine-derived urinary enzyme-phenotyping ratios","entity_type_key":"cellular_process"},"role":"target","stoichiometry":null,"state_label":"","sequence_order":1,"notes":""},{"entity":{"id":"8de34d8a-46dc-512c-a82f-d169747b496e","slug":"xdh","display_name":"Human xanthine oxidoreductase / XDH","entity_type_key":"protein"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":2,"notes":""},{"entity":{"id":"71ce8da8-6191-5375-b3cd-483d9b736b1c","slug":"1-methylxanthine","display_name":"1-Methylxanthine","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":3,"notes":""},{"entity":{"id":"d23cc5ec-08d0-51b9-bea4-74c5c3d0c357","slug":"1-methyluric-acid","display_name":"1-Methyluric acid","entity_type_key":"small_molecule"},"role":"context_participant","stoichiometry":null,"state_label":"","sequence_order":4,"notes":""}]},"contexts":[{"dimension":"evidence_access","value_text":"Primary abstract","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"experimental_model","value_text":"200 mg caffeine tests during allopurinol 300 mg/day for eight days.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"limitations","value_text":"The ratio is a context-dependent probe, not a direct measurement of dietary molybdenum.","comparator":null,"unit":null,"notes":"","entity":null},{"dimension":"nutrient_topic","value_text":"Caffeine collection; 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